Data storage systems (DSSes) store large quantities of data logically arranged onto many logical disks accessible to host devices. Host devices send data storage commands to a DSS in order for the DSS to access its storage and fulfill the data storage commands with respect to a logical disk. When a host device sends a write command as a data storage command directed at the DSS, the DSS writes data from the command to a block of a logical disk.
In some DSSes, logical disks are arranged as files on a filesystem internal to the DSS, allowing the logical disks to be provisioned with storage on-the-fly. This arrangement also allows for easy snapshotting of a logical disk at a given moment in time by sharing blocks between a primary filesystem file and various snapshot files.